Waterproofing of masonry walls



Aug. 3, 1937. A. L. LARSON I WATERPROOFING OF MASONRY WALLS Filed Dec. 9, 193a INVENTOR Arued L. Larson ATTORNEY Patented Aug. 3, 1937 1 I 2,088,754 WATERPROOFINGOF MASONRY WALLS Arved L. Larson, Bockville Centre, N. Y.

Application December 9, 1933, Serial No. 1,630

Claims. (Cl. 72-127) The present invention relates to water-proofing of masonry walls.

Brick walls, composed of brick and mortar, laid in the customary mannenhavebeen found to be so porous that some expedient mustbe resorted to for the exclusion of water. The bricks themselves areporous and cracksandse'ams of greater or less size are always present in the mortar. These seams are caused by carelessness in the laying of the mortar, shrinkage of the mortar, vibration, settling, or for'other reasons. The net result of these conditions is likely to be a leaky wall. Rain water, especially wheredriven by a hard wind, readily passes through these walls and ruins the finish applied to the walls.

Where no attempt is made to damp proof the wall itself, various expedients areresorted to to permit a dry surface to be had inside. The more common expedient is applying furring strips on the wall" and then some form 'of lathto which plaster, mastic, or other surfacing is -afllxed. These add to the expense and waste room space.

The present invention contemplates the waterproofing of the masonry wall by impervious sheet material which is inserted in place in the wall as the mason lays up the wall. This material is so thin as to make no difierence in the thicknessof the wall and is placed so as not to impair the load bearing properties of the wall. It is not 30 continuous through the height of the wall for such water-proofing would separate the wall into two partial walls and destroy cross bonding. The Water-proofing material is in pieces, each piece afiording protection to an area of the wall. Each 35 such piece extends through a part of a horizontal joint, preferably where header courses overlap downwardly to the next header course, and upwardly far enough to protect the. horizontal mortar joint to be left unprotected by the next higher 40 piece.

The preferred material for this water-proofing is a preformed length of ordinary asphalt roofing felt. It is cut to length, formed to a Z-shape and placed on parged parts of the brick wall so as to protect the same and is then buried in behind the outer bricks. This material is inexpensive, completely water-tight, and when laid with lapped joints, becomes self-sealing under the pressure in the wall.

Other and further objects of the invention will appear as the description proceeds.

The accompanying drawing shows, for purposes of illustrating the present invention, one of the many embodiments in which the invention may take form, it being understood that the drawing water-proofing.

. is illustrative of the inventionrather than limiting the same. In this drawing:

Fig. 1 is a perspective view illustrating, the building up of a brick wall embodying the present form of water-proofing, and 5 Fig. 2 is a perspective view of a water-proofing element. p 1 i In the drawing, the invention isillustrated in connection with the customary twelve inch American bond wall having'header courses 10 comprising an outer course of brick indicated at in and an inner course of brick indicated at l I, which overlap to provide a transverse bond, and. five courses of stretcher brick, the front brick being indicated at Ila-e, inclusive, the middle brick l5 l3a-d, inclusive, and the inner brick I la-e, in-. elusive. The mortar joints are indicated by the letter The invention is, however, applicable to English, Flemish,.or otherforms of bonded wall, and where thewall is more than 12 inches 20 thick, also to masonry walls having brick faces and tile backings. Y

In building up a solid brick wall it is first laid asto have the cross section indicatedat the right hand side of Fig. 1. Here it will be noted'that the 5 wall has" been completed at the bottom, and that a "stack of inner stretchers and intermediate stretchers have been laid up in mortar and covered over by acourse of inner headers ll.

In the drawing two additional courses of inner stretchers Ha, Mb are also indicated as having been laid. This is preferable'butnot an essential step in the preparing of a portion of the wall for The front surfaces of the'inner' headers and intermediate stretchers, as well as the front suriaces of the inner stretchers (where already placed) are parged as indicated at P. In doing this a thin coating of mortar is spread along these surfaces for a suitable length of the wall. The 40 wall is then ready for the Z-shaped water-proofing element W, which may be placed in position by the worker. These pieces are placed the entire length of this level of the wall and are preferably overlapped as indicated at 20. After they have been laid, the front stretchers and headers are laid up in mortar joints, as usual, to bring the front part of the wall up to the level'ot the next course of outer headers Ill. The inner and intermediate stretchers and inner headers are then built up again and parged to receive the next piece of water-proofingmaterial.

It will be noted that the water-proofing material herein shown extends downwardly through all the vertical mortar joints between two superposed headers as well as up-through the portion of the vertical Joint the inner stretchers immediately above the inner headers. In this way there is an overlapping of the vertical portions ofthe water-proofing means so that all the horizontal Joints'in the brick wall are protected and so that no watercsn possibly pass through the Various forms of thin sheet material'of an imperviousna'turennybeused. Insomecasesmetal sheet'is satisfactory but it is preferably provided with suitable corrugations or roughening so that mortar will adhere to it. The preferred material, however, is a preformed sheet of ordinary asphalt roofing, or tarred felt. This material comes in widths'which are convenient to handle and can be readily cut and bent to the desired shape;

overlapped edges are self-sealing'as the tarry surfacing of the roofing felt adheres under the pressure vwhich will be developed in the'wall. a

It will -be noted that'a wall waterproofed as above described. has unimpaired bearing strength and that-the cross bonding by regular brick to i mortar joints is carried out throughout a large part of the walL'lt will alsobe notedthat the water-proofing material does not completely destroy cross bonding. v

Where asphalt rooting. felt or similar materials are used, the wall is insured against the development of shrinkage cracks or seams, for the adhesion of mortar to these materials is not so great as to-prevent such slippage as will permit the water-proofing material. to stretch and accommodate itself.

Whatis claimed is: I v

i. A solid brick having header and stretcher courses in each face thereofwith the header courses thereof lapped transversely, there being horizontal mortar iointsbetween the courses of brick and vertical mortar jointsibetweenroppo- 1 site stretcher courses and between opposite header and stretcher courses. andimperforate water-.- proonng means extending across the portion of the horizontal joint between lapped header bricks,- downwardly. through the vertical mortar joint in-linie-withthe front face of the inner headers so as to cross all thehorizontal Joints above the next lower outer'header course ami terminding adiacentsaid lower header course, and upwardly-behind nthe;inner end of, the outer 1 header brick of the lapped courses andacross the horizontal mortar joint next above.

2. A solid brick wall having header and 1 ments of Z-shape. said elements being thin and occupying substantially the entire height or the vertical mortar joint spaces over the middle of the outer header courses, a portion in excess of one brick in height of the vertical mortar joint space above the middle of the inner header courses and the portion of the horizontal mortar joint space where the headers are lapped, whereby, water entering the wall through the front head and stretcher courses is prevented from passing to the'header and stretcher courses protected thereby;

3. A preformed,

l-shaped water-proofing element for brick walls consisting of a sheet of impervious. roofing felt bent to shape and having-a long vertical portion of a height equal to the height of a plurality of courses in a brick wall.

, a horizontal portion. equal to one half the length of a brick and extending rearwardly from the upper end of the vertical portion, and a short rear vertical portion whose height is greater than the thickness or a brick course and both'adlacent mortar joints for water-proofingthe inner portionsof brick walls which havestretcher courses interrupted by header courses. a

4. A solid masonry'wall having inner and outer faces and comprising header and stretcher courses of brick in the outer face and a masonry backing extending to the rear face. there being vertical mortar joints behind the stretcher coursesrhori zontal mortar Joints underneath the inner ends of header bricks and vertical mortar joints behind 'i the inner ends of the h'eader'bricks, said latter:

vertical mortar Joints extending upwardly above the header brick, and .a plurality of imperi'orate water proofing elements each extending upwardly through the first mentioned vertical mortar jdnt.

rearwardly in the adJacent; horizontal mortar joint and then upwardly through the second mentioned vertical mortar joint and terminating above the lower. edge of I the next water-proofing element'above.

5.'A solid nmsonry-wallfhaving-header and stretcher courses of brick in-v at least one face thereof and a backing all held together by mortar.

and impervious water-proofing elements of. Z-shape, said elements being thin and occupyingsubstantially the entire height of the vertical mortar joint space to the. rear of said stretcher. bricks, a portionin excess of one brick height of the vertical mortar iointatthe rear of the header joint under the rear end of theheader brick. whereby wateeentering thewall through said header and stretcher courses is prevented from v brick and the portion of the horizontal mortar 

